Stockholders' Equity and Employee Stock Option Plans RSU and RSA Activity (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
RSU and RSA activity [Abstract]
RSU/ RSA Nonvested and outstanding opening balance, Number	2,521,593	2,201,169	1,464,090
RSU/ RSA Nonvested and Outstanding Opening balance, Weighted Average Grant Date Fair Value	$ 8.40	$ 8.88	$ 10.52
RSU/ RSA, Grants in Period	700,987	1,381,070	1,628,183
RSU/RSA, Grants in Period, Weighted Average Grant Date Fair Value	$ 3.25	$ 8.74	$ 8.02
RSU/RSA Vested in Period	(977,149)	(580,075)	(722,806)
RSU/ RSA Vested in Period, Weighted Average Grant Date Fair Value	$ 8.48	$ 10.55	$ 10.06
RSU/ RSA Forfeited in Period	(315,817)	(480,571)	(168,298)
RSU/RSA, Forfeitures, Weighted Average Grant Date Fair Value	$ 7.80	$ 8.96	$ 9.76
RSU/ RSA Nonvested and outstanding ending balance, Number	1,929,614	2,521,593	2,201,169
RSU/ RSA Nonvested and Outstanding Closing balance, Weighted Average Grant Date Fair Value	$ 6.56	$ 8.40	$ 8.88
Total fair value of RSUs vested and released	$ 3.7	$ 5.1	$ 6.2
RSU, Vested and Expected to Vest, Outstanding, Number	1,793,546
RSU, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value	$ 4.4
Share Price	$ 2.45

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Share-based Compensation Arrangement by Share-based Payment Award, RSU, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, RSU, Vested and Expected to Vest, Outstanding, Number

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No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Price of a single share of a number of saleable stocks of a company.

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